A study is made by TEM, XRD and by measuring electrical/magnetic properties, of growth mode and properties of Pt1-xNix alloy films deposited on MgO(0 0 1) at 250 degreesC by de-sputtering at 2.5-2.7 kV in Ar. A bias voltage V-s less than or equal to -160 V was applied to the substrate during deposition. It was confirmed that the Pt film was polycrystalline with the texture of Pt(1 1 1)/ MgO(0 0 1) while the films of Pt0.14Ni0.86 and Pt0.19Ni0.81 were epitaxially grown with Pt-Ni(0 0 1)[1 0 0]/MgO(0 0 1)[1 0 0] similarly to the case of Ni/MgO(0 0 1). Thus the growth mode transformation between Pt-Ni(1 1 1)/MgO(0 0 1) and Pt-Ni(0 0 1)/MgO(0 0 1) may be induced at x less than 0.81 for Pt1-xNix alloy films. The temperature coefficient of resistance TCR from 100 to 300 K of Pt0.14Ni0.86 films was estimated to be 0.0044-0.0053 K-1 and saturation magnetization at 300 K to be 1.7-3.2 kG, respectively, while TCR of Pt films was estimated to be 0.0035-0.0048 K-1.